1. Field of Invention
This invention relates to the production of scents in conjunction with the display of video images
2. Description of Prior Art
There have been different attempts to produce scent in conjunction with moving images. The one generalization which can be made is that in contradistinction to this application all other related patents work by dispersing the scent into the air. This would mean that the scent had to be distributed throughout the entire volume of air of the room in which the viewer was seated.
In U.S. Pat. No. 1,749,187, the viewer sits in a movie theatre whilst a blower disperses scent from a tank into the entire theatre. There can be more than one tank used so that more than one fragrance is used. The valves are either hand operated or driven by solenoids. The actuating mechanism was a lever which follows precut grooves in the edge of the film.
U.S. Pat. No. 2,540,144 describes a system for producing scent in conjunction with images on a television. A signal is encoded into the broadcast TV signal by using a small focussed light in the original image field. The signal is decoded on the receiving end with a decoder which then triggers the release of different scents from valve controlled containers with the help of a blowing system.
In U.S. Pat. No. 2,562,959, there is a film reader which consists of photocells which are activated when the portions of the film with preprogrammed perforations occur. The activation of the photocells in turn leads to the activation of a mechanical gear and cam system which then in turn activates switches. The switches then activate solenoid operated valves which allows compressed air to enter the designated scent containing chamber. Then the scent is dispersed into the air.
In the U.S. Pat. No. 2,813,452 there are motor driven cells mounted on a wheel. The cells have valves which can be connected to rigid tubing overriding the cell. The tubing is solenoid activated. The cells are placed on a rotating table in a predesignated way.
U.S. Pat. No. 2,905,049 describes a system for movie theaters to disseminate scents coordinated with the movies. This system uses a train of fragrance "batteries". The batteries are pulled along in a predetermined sequence. When the designated battery comes underneath a valve system the scent from that battery is drawn into the ventilating system and dispersed into the theatre.
In U.S. Pat. No. 3,795,438 another device is described to distribute scent into a movie theatre. Again there are scent containing cartridges which are moved into position to be in line with a ventilating system so that the scent is dispersed. The authors give a wide range of thresholds for scent detection 10 exp 4 to 10 exp -3 mg/100 m3. This wide range of concentration underscores the difficulty of maintaining a consistent scent threshold when the scent is to be distributed throughout a room.
In U.S. Pat. No. 4,603,030 there is another system of scent cartridges which are lifted one by one from a rotating wheel up to a duct system which blows air through it and then distributes the scent laden air into the room. The duct connects with a vent system which leads to the backs of theatre seats at a cinema where it is then emitted into the air. The system is computer controlled. The scent is in solid form.
The final U.S. patent number in this list is U.S. Pat. No. 4,629,604. This is a multiaroma cartridge player. It consists of a partitioned box with individual heating elements for the different partitions which heat the separate scent discs in each partition. The scent discs are mounted on one cartridge which is loaded into the player as one unit. The system is controlled by an electronic interface which is connected to a video player.
In U.S. Pat. No. 3,795,438 it is stated the invention is based on the recognition that, in order to obtain a controlled distribution of odour, as little of the odorous substance as at all possible has to be introduced and the odorous substance has to be quickly removed again . . . " This highlights a problem common to all the systems described in this prior art section. The problem is that all these systems must disperse the scent into a relatively large space(eg. a room or movie theatre). This puts a great demand on the system.
The first demand is that the system must distribute a relatively large amount of fragrance into an open space. Because concentrations in the delivery unit have an upper limit this can only be accomplished by using relatively high volumes of scent laden air. The second demand is mixing. The system must deliver the scent uniformly distributed throughout the room simultaneously to all parts of the room. Anyone familiar with diffusion and convention phenomena knows that accomplishing this feat even in a modest size room is difficult. The final difficulty is being able to change over from one scent in the room to a different scent as rapidly as the scenes on the screen change.